I don't think order matters that much. In my case I didn't even clip anything, just put things in the envelope in some sort of order, i.e. all the N-400 together, the copy of the GC (Green Card) the pictures (in their photo store envelope) and the check.
At the least I think you should include also a photocopy of both sides of your GC. Check the guide to naturalization as suggested.
My 2 cents.